Ωhm

Try by using air pressure. BEWARE OF FLYING OBJECTS.

Suspect starter motor. Welcome to the forum.

Engine Speed Sensor = Crank Position Sensor (CPS).

What a great unit to own. How's your display? Mine needs bulbs.

Proud owner of the Sansui RA500 reverb unit.

AKAI. That when I stopped buying vinyl and started bootlegging all my friends Rock stuff.

My days of collecting 45's/Albums was the early, too mid 60's. Motown sound (Gordy, Soul, Motown & Tamla labels). Records have stood in storage so long now there probably flat on one side.

Right hand side of engine compartment, mounted on a bracket, should have yellow caps on them.

Closed Throttle Switch (CTS). Tells ECU throttle is closed. With KEY OFF, connect ohmmeter between D2-7 and D2-13. Push the plunger in and out. Does ohmmeter show switch is operating properly?

Good news (lucky you) on having that original ECU. Good call, after proving everything else looked good (love your REM) and swapping ECU's. I'd still be on the lookout now for 89-90 ECU again.

CPS fix was to bypass C101 and wire directly to the ECU. Can you back track the loose wires to C101 and determine there pin locations?

Does your Crank Position Sensor (CPS) wires run directly to the ECU?

Isolate the Radiator Temperature Switch. Disconnect switch. On the component side, run Fused B+ to a bulb, then to C243_B. Ground C243_A. Place bulb in a location where you can see it. Determine if Radiator Temperature Switch ever switches. Could determine which side of this issue is giving you your grief.

You removed the fuel pump relay, hot wired pin 87, started engine, engine dies. Was the fuel pump still running after the engine died?

Year?? Engine??

Add possible lower radiator hose collapsing. Give it a squeeze.

WELLS spec sheet: Normally Open Circuit; Closes at 198°F ±9°F.

No Should be C243. Lower radiator.

Do you mean C214_B?

Don't know about TSB number. I.S. 32E is the Fuel Pump Noise number.

No ballast OK. But I would suggest you swap the wires (1(30) with 5(86)) on your O2 Heater Relay. Currently your O2 heater circuit current flow through your IGN SW (12vdc/6ohms=2amps) with KEY ON. This 2amps is above everything else that flow through the IGN SW. One upon a time, when MS1700 was the tester of choice, vehicle would have failed and the fix was this swap. Also if ballast resistor was installed, part of the instructions was to include this swap. Suggestion only, feel free to ignore.

That a good starting point.

Okay. They had a kit (fuel pump noise) out there where one could add a ballast resistor. This included the O2 heater relay update.

This show O2S has slow response time. Should flicker LEAN/RICH at the speed of light. Less than 128 takes fuel away (decreased INJ PW time). O2 sensor see a RICH condition.

Your wired according to the 88 Elect Manual schematic. That is IGN feed (YEL) to pin 1(30) and FP relay feed to 5(86). Do you have a ballast resistor?